Method of cutting



R. EASTON.

METHOD OF CUTTING March 18, 1958 Filed Dec. 12, 1956 ilt;

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"tinned States Patent 6 ll IETHOD 0F CUTTING Rufus Easton, Pittsburgh, Pa., assignor to Koppers Com pany, Inc a corporation of Delaware Application December 12, 1956, Serial No. 627,824

6 Claims. ((3. 148-96) This invention relates to the cutting of metal castings and more particularly to a method of cutting continuous vertical castings of steel by means of gas-fiamecutting streams directed against the vertical castings from cutting torches.

in the continuous casting of steel to produce selected lengths of steel casts, it has been customary to cut the castings into selected lengths by means of one or two cutting torches. Since the cutting process has had to be continuous in order not to interfere with the overall continuous casting operations, it has been found desirable to use a process which would be dependable and free from constant failures. Although a number of processes have been developed in an attempt to meet these requirements of performance, these processes have proven to have their disadvantages. For one, they have been limited with respect to the time required to execute them. Further, they have required many adjustments in order to effect efiicient operation. For example, even those more desirable past processes which have included the use of two cutting streams operating in the same plane necessarily have been limited in their speed of operation, since rapid movement of the cutting streams has resulted in drag angles which have been so excessive as to prevent proper severing of the casting. To avoid this at least in part, it has been found advantageous to adjust accurately the positions of the cutting streams in the same plane, one with respect to the other, within defined limits so that the metal remaining from the drag angle of one can be removed by the other. This operation, in addition to requiring great care in the adjustment of the apparatus from which the cutting streams emanate, necessarily has required an additional movement of the apparatus for one of the streams so that such apparatus might compensate for an operation which the apparatus for the other stream had not complated successfully.

The present invention avoids the above disadvantages, providing a process for cutting continuous vertical castings of metal which is rapid, straightforward, and efiicient in its operation. The present invention further provides a process w 1ch requires a minimum of preparation before its execution and one which is not restricted in its speed of performance.

Various other features of the present invention will become obvious to one skilled in the art upon reading the disclosure set forth hereinafter.

More particularly, the present invention provides a method of cutting a metal casting into preselected cast lengths which comprises moving gas flame cutting streams relative each other from positions at opposite edges of the casting, and directing the cutting streams in their movement to cut the casting in different upper and lower parallel planes, the planes being so spaced that upon overlapping of the cuts of the streams metal between such cuts is caused to be pulled into the lower cutting stream by the weight of cast below the cuts and severed by the cutting stream to thus separate such casts.

it is to be understood that various changes and modifications can be made by one skilled in the art in the several steps of the process set forth hereinafter without departing from the scope or spirit of this invention.

Referring to the drawings:

Figures 1, 3, and 5 are horizontal cross-sectional views schematically disclosing three successive positions of the cutting torches and the progress of cuts when severing a continuous vertical casting by a process wherein the cuts are made in the same plane and the cutting equipment is not accurately adjusted;

Figures 2, 4, and 6 are corresponding broken vertical views of the cutting position disclosed in Figures 1, 3, and 5 respectively;

Figures 7, 9, and 11 are horizontal cross-sectional views schematically disclosing three successive positions of the cutting torches and the progress of the cuts when severing a continuous vertical casting in accordance with the inventive process;

Figures 8, 10, and 12 are corresponding broken vertical views of the cutting positions disclosed in Figures 7, 9, and 11 respectively.

Referring to Figures 1 and 2 of the drawings, torches 2 and 4 from which gas-flame cutting streams emanate are disclosed as moving in the same plane, substantially parallel to themselves, and normal to one side of the metal casting 6.

In Figures 3 and 4, torches 2 and 4 are disclosed as having reached the limit of their inward movement toward each other, since the torches are positioned in the same cutting plane and any further inward movement 0 these torches toward each other would result in collision.

As can be seen in Figure 3 of the drawings, the severing of the cast has not been completed at this position since the drag angles of the cutting streams from the two torches have left a portion of casting 6 uncut. In Figures 5 and 6, torch 2 has been reversed in its motion, leaving room for torch 4 to continue its motion in the same direction. The operation still fails to cut away effectively the remaining metal left by the drag angles of the cutting streams. This is so since, with the cutting away of the metal portion immediately adjacent the tip of torch i, the cutting stream no longer drags behind the direction of movement of that torch but moves to the path already determined by the drag of the cutting stream from torch 2. Thus, the metal cast remains unsevered and the entire casting operation is interrupted.

Referring to Figures 7 and 8 of the drawings, torches 3 and 12 are disclosed as positioned in different cutting planes, each of the torches moving parallel to itself and inward toward the other in a position substantially normal to one side of metal casting 14. The gas-flame cutting streams provided by torches S and 12 are advantageously of the oxy-acetylene type but it is to be understood that other type gas-flame cutting stream can be used. It is also to be noted that the planes in which the cutting streams from torches 8 and 12 emanate are so spaced that upon overlapping of the cuts of the streams (as described hereinafter), metal between such cuts is caused to be pulled into the cutting stream from torch 12 by the weight of cast below the cuts and severed by this cutting stream to separate such cast. in an advantageous embodiment of this invention, it has been found desirable to space these planes so that the center lines of out are approximately 1 to 1 times the width of cut from each other. It is to be understood that this spacing can vary within limits determined by the mass of cast below the cuts.

Referring to Figures 9 and 10 of the drawings, torches 3 and 12 are shown as having reached the same position as shown for torches 2 and 4 in Figures 3 and 4. At this point in the inventive process, it is possible to continue movement of each of the torches in the same direction torches to pass each otherwiithout any interference tudinal axes converge slightly inward toward ess, and that such positioning need a separate such cast.

' 3 from which it was initially started so long as the planes of the cutting streams are so spaced that the center lines of 'the cuts are positioned away from each other a distance This permits the When the torches move past each other so that the cuts formed by the cutting streams of each of the torches overlap, the weight of metal below the cuts causes metal between the cuts. to be pulled into the lower cutting stream and slightly greater thanthe width of cut.

severed to separate the cast below the cuts. In the event the cutting planes are not spaced sufficiently far apart as to permit free movement of other, one of the torches can be with drawn to allow the other to continue its motion in the same direction, Thus, the overlapping of cuts is effected and the cast is'separated (Figures 11 and 12). i i i In carrying out the inventive process it has been found advantageous to move the cutting streams from the torches at a rate of about 12 inches per minute. However it is 'to be understood that the rate of movement can vary advantageously anywhere from approximatelyrtS inches cast lengths comprising moving oxygen cutting streams relative each other from positions at opposite edges of said casting, and directing said cutting streams in their movement to out said casting in different upper and 7 lower parallel planes which are so spaced that upon overlapping of the cuts of said streams metal between such cuts is caused to be pulled into the lower cutting stream by the weight of cast below the cuts and severed by such cutting stream to separate such cast.

2. A method of cutting metal casting into preselected cast lengths comprising moving oxygen cutting streams relative each other from positions at opposite edges of said casting, and directing said cutting streams in their movement to out said casting in different upper and lower torches 3 and 12 past each i it is to be' streams in their movement to out said casting in diiferent upper and lower parallel planes which are so spaced that upon overlapping of the cuts of said streams metal between such cuts is caused to be pulled into the lower cutting stream by the weight of cast below the cuts and severed by such cutting stream to separate such casting.

4. A method of cutting a vertical continuous casting of molten steel comprising moving oxygen cutting streams relative each other'from positiohs at'opposite edges on the same side of said ast n a d direct said uttin streams so as to be convergent toward each other and in their movement to out said casting in diiferent upper and lower parallel' plan'es so spaced that upon overlapping of the cuts of said streams metal between such cuts is caused to be pulled into the lower cutting stream by the weight of cast below the cuts and severed by such cutting stream toseparate such cast.

5. A method of cutting metal casting into preselected cast lengths comprising simultaneously moving a pair of;

' oxygen cutting streams toward each other from opposite edges of said casting, directing said cutting streams in their movement to out said casting in different upper and.

lower parallel planes which are so spaced that upon over-- lapping of the cuts of said streams metal between such cuts is caused to be pulled into the lower cutting stream by the weight of cast below the cuts, reversing the direction of movement of one of said streams before the cuts of said streams overlap, and continuing the movement of the other of said streams'so that said cuts overlap, whereby metal between such cuts is pulled into the lower cutting stream and severed thereby and the cast below. the cuts is separated.

6. A method of cutting a continuous vertical casting of molten steel comprising simultaneously moving a pair of oxygen cutting streams toward each other from opposite edges on the same side of said casting, directing said cutting streams so as to be convergent toward each other and in their movement to out said casting in difierent upper and lower parallel planes which are so spaced that parallel planes which are so spaced that the center lines of out are approximately 1 to 1 /2 times the width of cut from each other so that upon overlapping of the cuts of said streams metal between such cuts is caused to be pulled into the lower cutting stream by the weight of cast below the cuts and severed by such cutting stream to p 3. A method of cutting metal casting into preselected cast lengths comprising moving oxygen cutting streams relative each other from positions at opposite edges on the same side of said casting, and directingsaid cutting the center lines of out are approximately 1 tol /2 times the width of cut from each other, reversing the direction" of movement of one of said streams before the cuts of said streams overlap, :and continuing the movement of the other of said streams so that upon overlapping of the cuts ofsaid streams metal between such cuts is caused to be pulled into the lower cutting stream by the weight of .cast below the cuts and severed by such cutting stream to separate such cast.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A METHOD OF CUTTING METAL CASING INTO PRESELECTED CAST LENGTHS COMPRISING MOVING OXYGEN CUTTING STREAMS RELATIVE EACH OTHER FROM POSITIONS AT POSITE EDGES OF SAID CASTING, AND DIRECTING SAID CUTTING STREAMS IN THEIR MOVEMENT TO CUT SAID CASTING IN DIFFERENT UPPER AND LOWER PARALLEL PLANES WHICH ARE SO SPACED THAT UPON OVERLAPPING OF THE CUTS OF SAID STREAMS METAL BETWEEN SUCH CUTS IS CAUSED TO BE PULLED INTO THE LOWER CUTTING STREAM BY THE WEIGHT OF CAST BELOW THE CUTS AND SEVERED BY SUCH CUTTING STREAM TO SEPARATE SUCH CAST. 